General Relativity Explained in 7 Levels of Difficulty

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  • čas přidán 4. 06. 2024
  • Go to nebula.tv/minutephysics to get access to Nebula (where you can watch the extended version of this video), plus you'll get a 20% discount on an annual subscription.
    This video covers the General theory of Relativity, developed by Albert Einstein, from basic simple levels (it's gravity, curved space) through to the concepts of how curved spacetime is represented by psuedo-Riemannian manifolds with Lorentzian signature (that is, special relativity and minkowski space are the local tangent space), how matter and energy are represented by an energy-momentum tensor, and how these two together obey the Einstein Field Equations. The solutions to the Einstein Field Equations (including the schwarzschild metric, kerr metric, freedman-lemaitre-robertson-walker metric, etc) represent gravity around massive objects like the sun, earth, and black holes, but also the history and expansion and future evolution of the cosmos. The universe on a large scale is described by general relativity - on a small scale, quantum mechanics. And where they meet... there's still work to be done.
    REFERENCES
    Wald's textbook - General Relativity
    Hartle's textbook - Gravity: An Introduction to Einstein's General Relativity
    Carlo Rovelli History of Quantum Gravity: cds.cern.ch/record/442809/fil...
    Leon Rosenfeld 1930 paper on quantum gravity: www.edoc.mpg.de/438547
    Kerr Metric Solution - en.wikipedia.org/wiki/Eddingt...
    Schwarzschild Metric - en.wikipedia.org/wiki/Schwarz...
    Eddington-Finkelstein Coordinates - en.wikipedia.org/wiki/Eddingt...
    Support MinutePhysics on Patreon! / minutephysics
    Link to Patreon Supporters: www.minutephysics.com/supporters/
    MinutePhysics is on twitter - @minutephysics
    And facebook - / minutephysics
    And Google+ (does anyone use this any more?) - bit.ly/qzEwc6
    Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute!
    Created by Henry Reich
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Komentáře • 2,5K

  • @renerpho
    @renerpho Před 3 lety +9479

    To quote Enrico Fermi: "Having listened to your lecture I am still confused. But on a higher level."

    • @yeahminecraft1627
      @yeahminecraft1627 Před 3 lety +322

      Man, if that quote doesn't describe my 400 level physics classes so well.

    • @HeadCannonPrime
      @HeadCannonPrime Před 3 lety +70

      This captures my feeling precisely.

    • @portobellomushroom5764
      @portobellomushroom5764 Před 3 lety +216

      That's pretty much all learning though, just increasing the level you're confused at until you're the most confused one in the world

    • @YoshisaurUnderscore
      @YoshisaurUnderscore Před 3 lety +115

      @@portobellomushroom5764 At that point, you're so confused that the only way for you to be not confused is to make new discoveries in your field.

    • @ericeaton2386
      @ericeaton2386 Před 3 lety +84

      @@YoshisaurUnderscore I think you mean the only way to be confused in new and interesting ways is to make new discoveries in your field.

  • @VVilliamMinerva
    @VVilliamMinerva Před 3 lety +4271

    You know it's going to get serious when you're on 7 and the video is only half over

    • @Anvilshock
      @Anvilshock Před 3 lety +19

      Though, most of the latter part is sponsor fluffing these days anyways, so, it's not really that more serious.

    • @reisanibal1
      @reisanibal1 Před 3 lety +12

      Or... there are a lot of ads.

    • @christopherswanson5849
      @christopherswanson5849 Před 3 lety +7

      not to mention he was like "ima speak a little slower now"

    • @BullocK1495
      @BullocK1495 Před 3 lety +5

      It got serious for me at stage 4. I get inertia, I get the whole 'ball in the middle of a sheet' example, and I get that time is a series of snap shots, but WHY any of that stuff happens is totally beyond me.

    • @ivoryas1696
      @ivoryas1696 Před 3 lety

      Hunter Humphrey
      Serious = good in this case.

  • @moretto6575
    @moretto6575 Před 3 lety +2602

    "general relativity is a physics theory created by Albert Einstein"
    Me: hold on smart guy, take it easy.

    • @truebluekit
      @truebluekit Před 3 lety +25

      I must agree.

    • @ivoryas1696
      @ivoryas1696 Před 3 lety +76

      Gui
      Let's start simpler...
      a squared plus b squared equals c-squared.

    • @fynexjeralt4186
      @fynexjeralt4186 Před 3 lety +66

      @@ivoryas1696 woah there, shapes? i thought this was physics

    • @ivoryas1696
      @ivoryas1696 Před 3 lety +27

      @@fynexjeralt4186
      Lmao, that's low-key how I felt entering Pre-calc 😂🤔😐

    • @JayronWhitehaus
      @JayronWhitehaus Před 3 lety +2

      Hahahahahahahahahahaha 😂

  • @Sid-dm3sq
    @Sid-dm3sq Před 3 lety +874

    Trying to explain relativity to me
    In 7 levels
    In 6 minute video
    At 5 in the morning
    In 4 walled room
    In 3 dimensional world
    On 2 dimensional screen
    And in 1 dimensional BRAIN
    NICE TRY👍

  • @StratosFair
    @StratosFair Před 3 lety +1275

    0:06 : What you study in class
    1:53 : What you get for homework
    4:30 : The exam

    • @sravanboi4205
      @sravanboi4205 Před 3 lety +46

      I can certify your comment. Its accurate

    • @peppatheoof
      @peppatheoof Před 3 lety +48

      "You went over it briefly 3 years ago, so now in this class we only review it"

    • @morthostalisint1720
      @morthostalisint1720 Před 3 lety +9

      This is, indeed, correct.

    • @-x-3694
      @-x-3694 Před 3 lety +9

      This comment has to be pinned 😂

    • @wellshit9489
      @wellshit9489 Před 3 lety +7

      Its in the small text on the side that they never tell you to read or acknowledge at all in my experience

  • @janmelantu7490
    @janmelantu7490 Před 3 lety +718

    7 levels, in 6 minutes. Less than a minute per level. Truly living up to the name “minutephysics”

    • @jasonlast7091
      @jasonlast7091 Před 3 lety +20

      That's cool but also level 7 was about half of the video (2:58)

    • @ivoryas1696
      @ivoryas1696 Před 3 lety +2

      jan Melantu
      "It's what I do."

  • @gman21xx
    @gman21xx Před 2 lety +331

    3:20 is my favorite part because I love how he lists off the numerous observations that validate the model. It's the observations that make this a physics theory instead of just mathematics.

  • @colinkennedy1718
    @colinkennedy1718 Před 3 lety +158

    2:22 "Oh that isn't too bad"
    2:24 "Oh it's actually 10 equations, ok"
    2:25 "Oh god oh f*ck"

    • @mbrusyda9437
      @mbrusyda9437 Před 2 lety +10

      Even the 2:25 is still the shortened form...

    • @DannySullivanMusic
      @DannySullivanMusic Před 2 lety

      hahaha man best comment ever

    • @prodbytukoo
      @prodbytukoo Před 2 měsíci

      10 non-linear partial differential equations, I mean, good luck man

  • @veritasium
    @veritasium Před 3 lety +3320

    Thanks for recommending Vitamania Henry!

    • @Zeegoku1007
      @Zeegoku1007 Před 3 lety +19

      Sup my brotha 😂

    • @fastyfoxy
      @fastyfoxy Před 3 lety +24

      BRO I LOVE YOU TWO GUYS

    • @davidmin3583
      @davidmin3583 Před 3 lety +8

      The check mark looks so suspicious I was about to report this account

    • @Spiros219
      @Spiros219 Před 3 lety +7

      Hey Derek, would you like to make a video explaining the differences between making curiositystream, CZcams originals and casual veritasium videos

    • @stevenalexander6262
      @stevenalexander6262 Před 3 lety +2

      I was here

  • @mmukulkhedekar4752
    @mmukulkhedekar4752 Před 3 lety +1410

    my two brain cells have been stuck on level 2 since past 5 years

  • @kummer45
    @kummer45 Před 2 lety +57

    I've been studying this for years. This is by far one of the most accurate videos on the field. Level seven is the strict construction of the equations and their solution throughout classical differential geometry, tensor calculus, complex analysis, linear algebra, ordinary differential equations, partial differential equations and special functions among the classical fields.
    This is simply a compendium of what this is in its entirety. This is the field of Riemann Manifolds.

  • @beverlymarsh9325
    @beverlymarsh9325 Před 3 lety +46

    It is so confusing that me, my future and past self gathered together yet couldn't understand anything

  • @davidbarnett8617
    @davidbarnett8617 Před 3 lety +1076

    The image of the black hole was not from the center of the Milky Way but rather from data collected observing the galaxy M87.

    • @TroyEagan
      @TroyEagan Před 3 lety +73

      I came here to say this.

    • @MichaelLesterClockwork
      @MichaelLesterClockwork Před 3 lety +87

      I came here to say exactly that... #copypaste
      "One of the largest known supermassive black holes, M87* is located at the center of the gargantuan elliptical galaxy Messier 87, or M87, 53 million light-years (318 quintillion miles) away."
      Sagitarrius A* is the one in the middle of the Milky Way, it is about 20,000 light years away, but obscured by all the dust in between.

    • @grantweldon6507
      @grantweldon6507 Před 3 lety +26

      Also was going to say this. Worth nothing that GR has been tested by other groups using the orbits of stars around Sagittarius A*

    • @capitalm417
      @capitalm417 Před 3 lety +23

      He corrected that in the video. 3:42

    • @portobellomushroom5764
      @portobellomushroom5764 Před 3 lety +1

      I made the same mistake myself when mentioning the 2020 nobel prize in physics and the 2019 photographed black hole

  • @angga2oioi
    @angga2oioi Před 3 lety +677

    The time I spent watching pbs spacetime did not goes to waste. I manage to nod at the explanation up to level 3. 🎉🎉🎉

    • @carloshernandezperez6963
      @carloshernandezperez6963 Před 3 lety +44

      I felt that.

    • @l1mbo69
      @l1mbo69 Před 3 lety +9

      @Charles Clarke bruh that's literally just a full course on GR

    • @l1mbo69
      @l1mbo69 Před 3 lety +2

      @Charles Clarke actually I do know about the ScienceClic YT channel, and yeah it's great! Just the perfect level for me

    • @mace1234
      @mace1234 Před 3 lety +2

      Omg I love spacetime! I didn’t realize it was so popular

    • @wyatttomlinson3475
      @wyatttomlinson3475 Před 3 lety +1

      I understand Level 6.5 stuff.
      But wait...THERE'S MORE!
      That's why I love physics!

  • @dreadnoughtus2598
    @dreadnoughtus2598 Před 3 lety +50

    3:42 That's not the black hole at the centre of the Milkyway. It literally says M87 on the picture!

    • @Alpinwolf5
      @Alpinwolf5 Před 3 lety +7

      YEP. Came looking for this comment.
      (Tho MinutePhysics still does a great job!)
      "Further reading":
      M87* is the SMBH at the middle of the Virgo A galaxy (a.k.a. M87). Our own SMBH in the Milky Way is Sagittarius A*. And the "star" part is important to the name - one does not simply leave it off.

    • @dreadnoughtus2598
      @dreadnoughtus2598 Před 3 lety +2

      @@Alpinwolf5 so does that mean you do agree with me

    • @Alpinwolf5
      @Alpinwolf5 Před 3 lety +3

      @@dreadnoughtus2598 yeah, totally! I only added more detail for other passing readers. :)

    • @dreadnoughtus2598
      @dreadnoughtus2598 Před 3 lety +2

      @@Alpinwolf5 thanks for your support in this matter. It is greatly appreciated.

    • @dreadnoughtus2598
      @dreadnoughtus2598 Před 3 lety +2

      @@connorgolsong290 which was.......?

  • @einstein4all
    @einstein4all Před 3 lety +56

    Words cannot express your talent and I'm so grateful. Thank you for all these insights and inspiration. It took me ~1000 hours to produce 17 hours of video explaining Special Relativity in just 3 levels of complexity …

  • @edawgrules
    @edawgrules Před 3 lety +682

    This is the kind of stuff that originally bothered me about science: that you have to keep coming back to a topic in order to learn the next stage as your level of understanding increased. Now, as a biology teacher, it is one of the things that makes science, and learning in general, fun. "Remember how you learned in middle school that plants make energy from sunlight? Well it's actually more complicated than that." "Remember how you learned in high school that plants make monosaccharides from sunlight? Well it's actually more complicated than that."

    • @Cosmalano
      @Cosmalano Před 3 lety +101

      I take the view that this is because everything in science is an approximation. The approximations get more accurate, Newtonian gravity, general relativity, whatever quantum gravity might be, etc. but they never become statements about the state of being of nature. Only nature itself a knows how nature is. And science merely concerns what we can say about nature.

    • @adnanchinisi7871
      @adnanchinisi7871 Před 3 lety +14

      @@Cosmalano completely agree with your statement about us never knowing the absolute truth/ exact way something works. Personally, I would switch "nature" for "God" but to each their own.

    • @tattwa1
      @tattwa1 Před 3 lety +51

      @@adnanchinisi7871 God? lol

    • @cecilbrisley5185
      @cecilbrisley5185 Před 3 lety +73

      @@tattwa1 Aw c'mon. God is just the standard thing we stuff in all the gaps of our knowledge. Each time we learn something new, we yank the god out of that gap and stuff it into the next.

    • @CArnoldi1
      @CArnoldi1 Před 3 lety +6

      @@Cosmalano This is also one of the core tenets of Kants philosophy.
      en.wikipedia.org/wiki/Transcendental_idealism

  • @blackpete
    @blackpete Před 3 lety +675

    Level -1: falling Apple + head = ouch.

    • @Epilogue_04
      @Epilogue_04 Před 3 lety +27

      Newton level: fallin apple + head = gravitational universal law

    • @blackpete
      @blackpete Před 3 lety +3

      @@Epilogue_04 Oh, what's Steven hawking Level then?

    • @pclouds
      @pclouds Před 3 lety +5

      I like this level. And I'm hungry.

    • @isaacnewton7424
      @isaacnewton7424 Před 3 lety +7

      Lol

    • @WaveOfDestiny
      @WaveOfDestiny Před 3 lety +2

      Level -1.5
      ground = good
      Not ground = ouch

  • @EliasDam
    @EliasDam Před 3 lety +9

    This is a brilliant idea! To present such an advanced subject in different levels next to each other, it really makes it easier to follow

  • @jannesvanquaillie9151
    @jannesvanquaillie9151 Před 3 lety +13

    This was SOOOOOO good!
    Hearing all the explanation after one another really helped me to understand it!
    It's also kind of funny when you realise that level 1-6 is only the first half of the video XD.

  • @daviddavis4885
    @daviddavis4885 Před 3 lety +3719

    Level 14 of General Relativity: Obtaining a PhD in Theoretical Physics

    • @aryamanmishra154
      @aryamanmishra154 Před 3 lety +102

      Not neccesarily. Anyone with a class in GR can understand most of it. PhD in Theoretical Physics is much more sophisticated it develops on already developed GR and Quantum fields theory for example trying to develop parts of string theory.

    • @qazwerty41339
      @qazwerty41339 Před 3 lety +215

      I have a theoretical degree in physics

    • @denverbeek
      @denverbeek Před 3 lety +154

      @@qazwerty41339 I have a physics in theoretical degree.

    • @ishworshrestha3559
      @ishworshrestha3559 Před 3 lety +2

      Nicee

    • @dhirendrasingh2513
      @dhirendrasingh2513 Před 3 lety +45

      @@denverbeek I have theoretical in degree physics

  • @FarhanHafizh
    @FarhanHafizh Před 3 lety +441

    Level 3: Okay, kinda get the main idea
    Level 4: what

    • @dillon1012
      @dillon1012 Před 3 lety +1

      Not liked because number 69 likes

    • @user-rc8bb7yb1e
      @user-rc8bb7yb1e Před 3 lety +1

      really

    • @parahumour4619
      @parahumour4619 Před 3 lety +3

      @@user-rc8bb7yb1e dude you have a cool name

    • @dsdy1205
      @dsdy1205 Před 3 lety +4

      Just ignore the word salad and listen to the stuff he says after that, it makes more sense; I feel he shouldn't have led with the proper scientific name

    • @ballin1006
      @ballin1006 Před 2 lety +2

      @@dsdy1205 Ikr but now I can show off to everyone by knowledge of a pseudo-riemannian manifold is

  • @emirhanulas4281
    @emirhanulas4281 Před rokem +3

    I have been trying to understand it for a long time and this video put everything that I have found in a correct order and now I finally did understand it. AMAZING

  • @vaedkamat484
    @vaedkamat484 Před 2 lety +3

    I like that you include geodesics, a major step in my learning.

  • @desert123100
    @desert123100 Před 3 lety +156

    The algorithm has not been kind to your channel, this is the first of your videos that has popped up for me in probably a year.

    • @Ansh77K
      @Ansh77K Před 3 lety +1

      @Pinco Palla yep that explains many things

    • @leeroy265
      @leeroy265 Před 3 lety +1

      Understanding you tube algorithms in 7 steps....
      .
      .
      .
      .
      .
      .
      .
      NO CHANCE

    • @pronounjow
      @pronounjow Před 3 lety

      @@leeroy265 TRENDING

    • @floop1108
      @floop1108 Před 2 lety +1

      Then subscribe, and get all the notifications. Win-win, for you and henry.

  • @mariovanderwal1695
    @mariovanderwal1695 Před 3 lety +409

    I'm level 7 for things that I know.
    I'm level 0 for things that I understand.

    • @badmintongo4832
      @badmintongo4832 Před 3 lety +5

      Ricci tensors, curvature scalars, antisymmetric tensor fields, Grassmann variables, Christoffel coefficients, diffeomorphism invariance, isotropic pressure in vacuum states with cosmological energy densities, nonlinearity distinguishment from e.g. Schrodinger's equation and Levi-Civita symbols.

    • @TheShamansQuestion
      @TheShamansQuestion Před 3 lety +4

      Is it weird that I'm the exact opposite: Level 0 for things that I know; Level 7 for things that I understand?

    • @srajanverma9064
      @srajanverma9064 Před 3 lety +3

      @@TheShamansQuestion He wants to understand the things which he doesn't understand while neglecting the others.
      You want to understand the things you already understand but in as much more depth as possible while neglecting others..

    • @TheShamansQuestion
      @TheShamansQuestion Před 3 lety +3

      @@srajanverma9064 very nice 👌🏻 you're right my want is there but I'd de-emphasise "want" and say it's more once I get knowledge, I can understand it deeply (and because I want to/go for depth), plus a sceptical, Socratic element of "I know that I know nothing" (but that is probably more relevant to "understanding" in this case, so might be wrong on that)

    • @jibbs_aim
      @jibbs_aim Před 3 lety +2

      You just summed up physics

  • @michaelmckinney3507
    @michaelmckinney3507 Před rokem

    I have just discovered your vids and they are unreal! The fast pace really suits hows racy my minds works its great 😁👍

  • @jojoviviator9258
    @jojoviviator9258 Před 3 lety +1

    Cool concept for a video. I especially enjoyed the "level 1 again" explanation of people's personal experience of gravity on earth in terms of your GR explanation.

  • @triteraerlangga7917
    @triteraerlangga7917 Před 3 lety +550

    and here I am trying to pretend that I understand

    • @michaelterrell5061
      @michaelterrell5061 Před 3 lety

      I j ow you’re joking but understanding is the easy part. The mathematics behind it is the hard parts, but as with anything practice makes perfect.

    • @seanleith5312
      @seanleith5312 Před 3 lety

      You don't invent a theory, do you?

    • @lonestarr1490
      @lonestarr1490 Před 3 lety +8

      Fake it until you make it

    • @real_nosferatu
      @real_nosferatu Před 3 lety +1

      And here i am, trying to pretend that i relate to you.

    • @karigucio
      @karigucio Před 3 lety +8

      this video makes you feel like it is explaining something, that you are just not getting. It is not honest in this matter. You're not supposed to understand what a Riemannian manifold is by hearing the term, don't feel bad about it.

  • @IForgetYourName
    @IForgetYourName Před 3 lety +471

    Having solved the Einstein Field Equations for a physics final in college, fuck. That is all.

    • @abelnolan9378
      @abelnolan9378 Před 3 lety +21

      what topics do you go over before learning about Einstein's field equations?

    • @jiagengliu
      @jiagengliu Před 3 lety +68

      @@abelnolan9378 differential geometry and differential equations, I believe

    • @underfilho
      @underfilho Před 3 lety +60

      @@abelnolan9378 differential geometry, you will need tensors too, and a bit of classical mechanics and differential equations

    • @northernskies86
      @northernskies86 Před 3 lety +100

      It takes at least a few hours to derive even the simplest solution (Schwarzschild solution) to the EFE by hand. A set of 10 highly coupled nonlinear differential equations makes even the most brilliant mathematicians cringe.

    • @rtg_onefourtwoeightfiveseven
      @rtg_onefourtwoeightfiveseven Před 3 lety +107

      I once had a professor that said "Everyone should curl up with a warm drink and spend an evening deriving the Einstein Tensor for the FLRW metric by hand at some point in their life". Needless to say, I haven't done that yet.

  • @steffenleo5997
    @steffenleo5997 Před 2 lety

    Danke schön Henry für dieses toll und sehr verständlich erklärtes Video... 👍👍.... Macht so weiter.... 👍

  • @markkennedy9767
    @markkennedy9767 Před rokem

    Really nice explanation of the equivalence principle and just a nice conceptual summary of GR.

  • @imdadood5705
    @imdadood5705 Před 3 lety +207

    Okay, time to change my LinkedIn description to “Physicist specialized in General Relativity”

    • @mastershooter64
      @mastershooter64 Před 3 lety +20

      same, I changed it to, "having a theoretical degree in physics"

  • @Alessandro_Nicotra
    @Alessandro_Nicotra Před 3 lety +107

    Here I am finishing my Master Thesis on a Loop Quantum Gravity topic and trying to write a nice overview of what have brought us this far. This video is so perfect now I want to put the link to it in my thesis instead of writing chapter 1.
    Great work.

    • @kamakaze5448
      @kamakaze5448 Před 2 lety +3

      Hey I have some doubts about lqg . Can I ask you ?

    • @Alessandro_Nicotra
      @Alessandro_Nicotra Před 2 lety +3

      @@kamakaze5448 Sure :)

    • @smugface9955
      @smugface9955 Před 5 měsíci +2

      It’s been two years since this comment, but I’m curious to hear more from someone who has worked under a master’s program. To be frank, I’m a mathematician so sometimes I jump to the mathematical properties of these theories rather then the physical. Having glossed over a few papers on LQG, my sense is that the quantization of space challenges the Reimannian geometry of GR in a controversial way? At the end of the day, these theories come down to their predictive qualities (last I heard there were promising but inconclusive findings from gamma-ray bursts)… what’s the story on LQG today? Is it still alive and kicking?

    • @gregorykafanelis5093
      @gregorykafanelis5093 Před 5 měsíci +1

      I leave this comment because I wanna hear his response

  • @swastikmajumder9483
    @swastikmajumder9483 Před 3 lety +59

    Nobody literally nobody:
    1st year Physics Undergraduates:I'm gonna unite GR&QM

    • @yashkrishnatery9082
      @yashkrishnatery9082 Před 3 lety +4

      I'm also a first year physics UG currently at hansraj college. Delhi university
      Which college you are from

    • @pulkitmohta8964
      @pulkitmohta8964 Před 3 lety +1

      @Swastik Majumder nice! I also want to get into an IISER. I am going to give the entrance exam this year (again, as I didn't clear it last year), and I hope to get into an IISER!

    • @pulkitmohta8964
      @pulkitmohta8964 Před 3 lety +1

      @@yashkrishnatery9082 what are you studying there?

    • @yashkrishnatery9082
      @yashkrishnatery9082 Před 3 lety +2

      @@pulkitmohta8964 I'm preparing for JEE
      Last year I qualified both exams but didn't took admission as I didn't got rank under 2000
      I didn't took any formal coaching last time so I dropped and preparing

    • @yashkrishnatery9082
      @yashkrishnatery9082 Před 3 lety +2

      @@pulkitmohta8964 at hansraj I'm studying nothing. I'm just focusing on JEE. I just took admission there as I was getting in almost all DU colleges

  • @thehungryphysicist368
    @thehungryphysicist368 Před 3 lety

    This is a fantastic video, and a very effective and engaging style of presenting it. Bravo!

  • @tonydai782
    @tonydai782 Před 3 lety +81

    3:42 The image is of the black hole at the centre of M87, not the Milky Way, hence the picture being labelled M87* instead of Sagittarius A*

    • @crackedemerald4930
      @crackedemerald4930 Před 3 lety +6

      I think they tried imaging it too but there's a bunch of junk in the way and they're about the same angular size so yea.

    • @liamchisari2191
      @liamchisari2191 Před rokem +1

      Came to the comments looking for this, glad I'm not the only one who noticed that it's M87 and not Sagittarius A star

  • @kennylex
    @kennylex Před 3 lety +156

    This is the ultimate video to confuse flat-earthers even more :-D

    • @DanielBrown-ob3dr
      @DanielBrown-ob3dr Před 3 lety +29

      and round-earthers too

    • @yannickchayer1609
      @yannickchayer1609 Před 3 lety +13

      I had a discussion with a friend who's into conspiracy stuff, for shits and giggles mostly mind you, about how in a very special way, yes, you can say that the earth is flat.
      Twas a fun talk haha

    • @Yora21
      @Yora21 Před 3 lety +20

      No. Flat earthers are immune to facts.

    • @TheReligiousAtheists
      @TheReligiousAtheists Před 3 lety +16

      You thought the *Earth* is flat?! Well guess what, even space and time aren't flat!

    • @bobkreme2175
      @bobkreme2175 Před 3 lety +1

      still stomping on those ants? lol

  • @Random-Access
    @Random-Access Před 3 lety

    This the BEST video I've watched about General Relativity!!

  • @stef10ziggy
    @stef10ziggy Před 3 lety

    This totally helped me understand. Great concept.

  • @rikhilnell2623
    @rikhilnell2623 Před 3 lety +153

    Remember when math and physics had numbers?
    .... yeah me neither

    • @kingplunger6033
      @kingplunger6033 Před 3 lety +2

      indices !

    • @FranciT98
      @FranciT98 Před 3 lety +44

      I'm firmly convinced taking a maths/physics course is about the most roundabout way of learning the greek alphabet.

    • @williamromero-auila7129
      @williamromero-auila7129 Před 3 lety +5

      I think I saw an 8 somewhere in the video, but it might have been an illusion

    • @calvindang7291
      @calvindang7291 Před 3 lety +2

      @@FranciT98 Hey, you do learn it pretty quickly.

    • @ngiorgos
      @ngiorgos Před 3 lety +11

      Non-mathematicians: wait, it's not about the numbers?
      Me: never has been (points gun)

  • @matrixmodexp
    @matrixmodexp Před 3 lety +331

    I am very glad he mentioned that GR is incomplete

    • @MorgurEdits
      @MorgurEdits Před 3 lety +11

      I guess that should still not be the main take away from the video.

    • @ngiorgos
      @ngiorgos Před 3 lety +28

      When you're one of the most successful theories in the history of physics, but people only mention you to explain how you can't answer questions you weren't made to answer.
      It baffles me that educators always do that when they talk about GR (but not as much with Quantum Mechanics). 99.99% of the people don't know these theories when they do apply. Why are we so fixed on the cases they don't apply?
      Edit: I'm not saying to ignore the gap in our therories or that it is not important or interesting. I just meant to say that when first learning about relativity it's no use focusing TOO much of your attention there from the beggining.
      It's a great goal to work towards solving those mysteries. But realistically, you can't do much before you learn GR properly. Be informed about it and use it as a motivation to learn GR. You'll get there when you get there. And if you're already there, you're awsome! ;D

    • @chrispitterle8831
      @chrispitterle8831 Před 3 lety +23

      @@ngiorgos When I hear that quantum mechanics and GR still need more work to make the 2 compatible, I feel excited. It tells me that there is more to discover. It helps teach that science is in fluctuation. It changes and improves. There are questions left to solve and WE could be the ones to solve it.

    • @ireallyhatemakingupnamesfo1758
      @ireallyhatemakingupnamesfo1758 Před 3 lety +11

      @@ngiorgos every scientific theory from over 200ish years ago has been proven wrong one by one, our current theories are more right in more circumstances, but they're still wrong. In another 200 years we'll look back on some of this stuff the way we do phlogiston or the luminous aether. General relativity is the best tool we have to understand spacetime, but it'll be replaced eventually by something even more accurate!!

    • @freeman7079
      @freeman7079 Před 3 lety

      anyone else think this was Music is Win?

  • @devynthorne6941
    @devynthorne6941 Před 3 lety

    the earth surface analogy was awesome. great work!

  • @HodsBroo
    @HodsBroo Před rokem

    simple yet complex, great work

  • @Pandaemoni
    @Pandaemoni Před 3 lety +57

    3:44 That is NOT "the black hole at the center of the Milky Way" (Sagittarius A*) that is the black hole at the center of galaxy M87. They did consider imaging Sagittarius A*, but that was ultimately not their target. Edit: It turns out I do not know how to spell "Sagittarius."

    • @GrayLynch
      @GrayLynch Před 3 lety +1

      That’s what you got out of this?

    • @Pandaemoni
      @Pandaemoni Před 3 lety +14

      ​@@GrayLynch No, that is a correction to a mistake they made in the video. In no way did I suggest that the video wasn't worth watching or is otherwise "ruined" as a result of their mistake; but if it were me and I made a mistake in a science education video, I would hope I would be corrected.

    • @hrgwea
      @hrgwea Před 3 lety

      I immediately noticed that error as well.

    • @alwaysdisputin9930
      @alwaysdisputin9930 Před 2 lety +1

      Yeah but fan fuct: we do orbit the M87 black hole

    • @pookispooks6968
      @pookispooks6968 Před 2 lety

      @@alwaysdisputin9930 have you got a source on that?

  • @ThierryTiramisu
    @ThierryTiramisu Před 3 lety +56

    1:20 that's a nice globe you got there.
    Me, an intellectual: actually, it's a pseudo-Riemannian manifold with Lorentzian signature,... But thank you! 😊

    • @isaackay5887
      @isaackay5887 Před 3 lety +3

      ..out of all of them......this made me laugh the most. Well done 😂

    • @badmintongo4832
      @badmintongo4832 Před 3 lety +2

      Nondegenerate symmetric metric tensor too. Establish the linear connection/Levi-Civita connection with use of Weyl spinors (helicity operators).

    • @ivoryas1696
      @ivoryas1696 Před 3 lety

      Dave P
      _IQ +10_

  • @brickssolved5367
    @brickssolved5367 Před 3 lety +1

    I love how equivalence principle is added in the subtitles.

  • @emirkayrak
    @emirkayrak Před 3 lety

    YAAAY do this more please! Great content

  • @skatheo2716
    @skatheo2716 Před 3 lety +370

    the funny thing is, he's only explaining it for those who already know.

    • @ngiorgos
      @ngiorgos Před 3 lety +27

      I wish it was possible to explain it for the ones who didn't know. I wish that every day

    • @ivoryas1696
      @ivoryas1696 Před 3 lety +9

      Skatheo
      Well beyond around level 4, yeah, but it's seems pretty okay otherwise.

    • @TheBlueWizzrobe
      @TheBlueWizzrobe Před 3 lety +14

      @@ngiorgos I think Vsauce's "Which way is down" video does a pretty good job. It gets more obtuse near the end and doesn't even get as high-level as this, but I like it a lot.

    • @ngiorgos
      @ngiorgos Před 3 lety +9

      @@TheBlueWizzrobe Yes, I loved that! And Veritasium's video "why gravity is not a force" is also an excellent presentation.
      But the best they can do is give an overview of the theory and some intuitive explanations. The maths are still untouchable, unfortunately.

    • @iankelley9302
      @iankelley9302 Před 3 lety

      I got to around level 5, then level 6 I only knew some of it.

  • @gasdive
    @gasdive Před 3 lety +7

    So good. I've tried so many times to explain the way the ground pushes you away from a straight line and I've never once passed understanding across. Now I can link to this video with the clear diagram, and maybe in future, I'll succeed in showing the beauty of this idea to others.

  • @aminelabidi6113
    @aminelabidi6113 Před 2 lety

    SOOOOOOOOO BEAUTIFUL..! thanks man.. Best explaining ever ♥

  • @surfinch
    @surfinch Před rokem

    Wow. This was great. Thank You 🙏

  • @Noah-nk3zz
    @Noah-nk3zz Před 3 lety +5

    Thanks for summing all that up in a short video. I've seen a lot of videos explaining GR/SR on different "levels" and this gives me a nice feel on where I stand in my understanding of the subject.

  • @minutodefisica
    @minutodefisica Před 3 lety +938

    👀

  • @A.Dajlida
    @A.Dajlida Před 2 lety

    Wow! This is great. Thank you!

  • @gabrielhermel6932
    @gabrielhermel6932 Před 3 lety

    Amazing explanation, thank you.

  • @mtg_phoenix698
    @mtg_phoenix698 Před 3 lety +171

    The video hasn’t started yet and I’m already confused.

    • @DragonKingGaav
      @DragonKingGaav Před 3 lety +4

      That's why there's this video! czcams.com/video/wrwgIjBUYVc/video.html

    • @guitargodthor2
      @guitargodthor2 Před 3 lety +1

      Just picture space-time as water flowing towards a drain that is moving on the seabed below.
      Now picture the water as rainbow colors that never mix together (stripes maybe) as they flow towards the drain.
      Now picture the drain as a sphere. The 2D nature of its opening is the diameter and the edge is the equator.
      Now put a leaf anywhere in or on the water, near or far. What happens to the leaf in the different places you put it?
      That is space-time... with one exception...
      A drain sends the water somewhere else whereas space-time is fixed in place so it doesn't go anywhere. Space-time is literally pulled inward (or rather pinched) by the mass of a planet, star or blackhole as they move through it and it unpinches the farther away it gets from point A while heading to point B.
      Like walking on a memory foam mattress with stuff all over it. Your feet are the mass and the mattress is space-time and the stuff falls towards your feet depending on where you are on the bed.

  • @Cosmalano
    @Cosmalano Před 3 lety +28

    Great video. Your videos got me interested in general relativity six years ago, and to this day I’m still trying to become a mathematical physicist so I can study quantum gravity. ❤️

  • @staliniumprojectile
    @staliniumprojectile Před 3 lety +8

    This is actually the best summary video I've ever seen on physics.

  • @Random-zw9nh
    @Random-zw9nh Před 6 měsíci

    You are so blessed to understand these things.

  • @farrankhawaja9856
    @farrankhawaja9856 Před 3 lety +10

    Wow that was very quick but so educational! Thanks so much!

  • @dontuserachelslurs
    @dontuserachelslurs Před 3 lety +43

    It's not a question of "when? " my dear Reggie, but "where?"

    • @ewutermohlen
      @ewutermohlen Před 3 lety +1

      It's the same thing with the concept of spacetime

    • @tanmaydeshmukh3517
      @tanmaydeshmukh3517 Před 3 lety

      No no both when n where n how much

    • @Think_Inc
      @Think_Inc Před 3 lety

      It’s about whenere/ wheren.

    • @shadesilverwing0
      @shadesilverwing0 Před 3 lety

      Metaphysics: it's not a question of "what?" my dear Reggie, but "why?"

  • @DanielDaniel-xz2yp
    @DanielDaniel-xz2yp Před 3 lety +15

    Level 90:
    Discovering a mathematical notation that encapsulates both General relativity and Quantum mechanics and winning the nobel prize

  • @SchmySeymour
    @SchmySeymour Před 3 lety

    I've been a Nebula subscriber for at least a year and I've never seen Minutephysics mentioned on the site under you said to go looking for it.

  • @squished1879
    @squished1879 Před 3 lety +27

    "very high level stuff" - like nobody has figured out how to do it yet

  • @aemmelpear5788
    @aemmelpear5788 Před 3 lety +14

    I have been subscribed to this channel for quite some time now, I initially got interested because of my great physics teacher in high school. Back then I did not understand most of the videos at a deeper level (so the primary target audience).
    After 3 1/2 years of studying physics, I have my GR exam on monday and can happily say: I knew everything in this video! And it makes me glad to finally be at a point where I do understand this stuff at a deeper level. It took quite some time, but I got there.
    Of course I am still just beginning to be a physicist and there is MUCH I don't know yet and MUCH and I don't know that I don't know yet. And I am excited and looking forward to finding it out!

    • @Lorachzwan
      @Lorachzwan Před 3 lety +2

      Keep it up and thanks for your service to science :D

    • @fischmann1746
      @fischmann1746 Před 3 lety +1

      Same story here.
      Such Videos brought me to physics. According to plan, I'll have my Bachelor in half a year.

    • @aemmelpear5788
      @aemmelpear5788 Před 3 lety

      @@fischmann1746 Then I wish you best of luck for your thesis! Do you already know in what area you will write it?

    • @fischmann1746
      @fischmann1746 Před 3 lety

      @@aemmelpear5788
      Thanks.
      I'll write a program that simulates a non-linear mechanical system and analyse it's behaviour. What system in precise isn't clear yet.
      Writing simulations in non-linear physics is pretty much the profession I want to finde myself in some day.

    • @aemmelpear5788
      @aemmelpear5788 Před 3 lety

      @@fischmann1746 Sounds great! Computational Physics is also one of my favorite areas!

  • @sirdurtle9519
    @sirdurtle9519 Před 3 lety +98

    I went into this video thinking, oh, that's cool, he'll explain it in incrementally more complicated ways so I'll be able to understand it by the end!
    Me at difficulty 2: huh

  • @albertmendoza8330
    @albertmendoza8330 Před 11 měsíci

    Just finished taking general relativity this quarter that passed, and I can honestly say that this is the hardest topic I've seen so far in my physics career, but also the most enjoyable.

  • @romangonzalezadrianmaurici6302

    This video: There are 7 levels of understanding gravity.
    Me: I can make it to level three, take it or leave it.

  • @calebkulfan2190
    @calebkulfan2190 Před 3 lety +37

    i'm gonna start calling the 90s the "nowdays"

  • @LucretiusDraco
    @LucretiusDraco Před 3 lety

    im new this channel is awesome! lots more ppl would love to learn about physics but we need more stuff like this I feel like when ppl don't think physics r cool it's might b bc they're not getting an explanation that's ez to understand

  • @konradfischer9462
    @konradfischer9462 Před 3 lety

    Awesome approach!

  • @JesseRon
    @JesseRon Před 3 lety +4

    Videos like this remind me of why I love physics.

  • @greentau
    @greentau Před 3 lety +8

    M87 is not at the center of the Milky Way! It’s in another galaxy about 50 million lightyears away.

  • @lookingglassknight139
    @lookingglassknight139 Před 3 lety +3

    This is amazing. I love seeing high level knowledge explained quick. I’ve had this idea for a while about predicting the future with all the variables of today. Ultimately it comes back the is anything actually random and to that quantum mechanics says yes

  • @Bentami
    @Bentami Před 2 lety

    yeah.. this is something I definitely have to research more for a better understanding

  • @mr2octavio
    @mr2octavio Před 3 lety +32

    Today we have a Rover landing and minute physics uploaded, blessed day

  • @anubhavsrivastava1471
    @anubhavsrivastava1471 Před 3 lety +19

    Loved the level 0, something Einstein did 😂😂

    • @badmintongo4832
      @badmintongo4832 Před 3 lety +1

      Ricci tensors, curvature scalars, antisymmetric tensor fields, Grassmann variables, Christoffel coefficients, diffeomorphism invariance, isotropic pressure in vacuum states with cosmological energy densities, pseudo-Riemannian manifolds, nonlinearity distinguishment from e.g. Schrodinger's equation and Levi-Civita symbols.

  • @premdattpandey6960
    @premdattpandey6960 Před 3 lety

    Thank you for described level by level.

  • @kevinkent9194
    @kevinkent9194 Před 2 lety

    Thanks for the video.

  • @ThierryTiramisu
    @ThierryTiramisu Před 3 lety +3

    4:02 what a great explanation of gravity!:)

  • @lustyworldlivenow3186
    @lustyworldlivenow3186 Před 3 lety +25

    4:48 'Nowadays' ends at 1997, wonder when the next breakthrough will b e

  • @wyatttomlinson3475
    @wyatttomlinson3475 Před 3 lety

    You know what the insanely insane (and awesome) part of this video this? THERE'S MORE LEVELS!
    (For reference, I think I'm at 6.5, or at least between that and level 7. The idea of manifolds and tensors is something I have yet to understand, but I understood the rest of Level 7).

  • @shuraba1234
    @shuraba1234 Před rokem

    Thanks for subtitles

  • @misakamikoto8785
    @misakamikoto8785 Před 3 lety +12

    What is General Relativity?
    Level 0 answer: "posts this youtube link"

  • @andy-kg5fb
    @andy-kg5fb Před 3 lety +3

    the best gr guide on CZcams

  • @iPsychlops
    @iPsychlops Před 2 lety

    I love your videos! Please communicate to nebula creators that we NEED to be able to play videos at 2+x speed. I would spend so much more time there if I wasn't able to watch twice as much here in the same time.

  • @Kamari333
    @Kamari333 Před 3 lety

    another great video!

  • @mingminggg
    @mingminggg Před 3 lety +11

    I literally have to do a research paper on general relativity, thanks so much.

  • @vishnus.p.4007
    @vishnus.p.4007 Před 3 lety

    First of all very good video you have made here!!! Great.
    Secondly i would like to make a correction that the image of the blackhole is not that of the blackhole at center of milky way but is that of blackhole at center of M87.

  • @shadowambush711
    @shadowambush711 Před 3 lety

    This is great. Thank you

  • @enderwiggins8248
    @enderwiggins8248 Před 3 lety +3

    Riemannian manifolds are on the syllabus for my differential geometry course, so hopefully I gain a better appreciation for this video in three months

    • @ngiorgos
      @ngiorgos Před 3 lety +2

      The best of luck! Just be aware of the difference between Lorentzian and Riemannian manifolds. Riemannian manifolds are locally Euclidean spaces. Lorentzian manifolds are locally Minkowski spaces

    • @TheShamansQuestion
      @TheShamansQuestion Před 3 lety +1

      let us know in 3 months and tag us. keen to hear it from someone active going through the process

    • @nayankumarbarwa4317
      @nayankumarbarwa4317 Před 3 lety

      Now did you get it?

  • @deadoira
    @deadoira Před 3 lety +3

    05:09 „It is very high-level stuff“
    Our math teacher when creating the tests: „Haha what did you say? Pathetic.“

    • @wellshit9489
      @wellshit9489 Před 3 lety

      I like your quotation marks

    • @deadoira
      @deadoira Před 3 lety +2

      @@wellshit9489 I'm Russian so it explains everything

    • @wellshit9489
      @wellshit9489 Před 3 lety +1

      @@deadoira I wasn't being sarcastic dw, we have them in Iceland where I live too

    • @deadoira
      @deadoira Před 3 lety

      @@wellshit9489 I know, just decided to explain :)

  • @alanrodriguez7988
    @alanrodriguez7988 Před 2 lety +1

    Beautiful!!.

  • @lielyakobian319
    @lielyakobian319 Před 4 měsíci

    beautiful explanation

  • @Koisheep
    @Koisheep Před 3 lety +9

    Finally, I knew taking a course in differential geometry would be useful someday.

  • @alexyu8951
    @alexyu8951 Před 3 lety +5

    Can u do a general relativity series just like special relativity but like longer? Please?

    • @underfilho
      @underfilho Před 3 lety

      general relativity is really another level, but if you think that you have a good understanding in special relativity, the PBS Space Time has a playlist "Curved Spacetime and Gravity" or something like that, its really good

    • @underfilho
      @underfilho Před 3 lety

      czcams.com/play/PLsPUh22kYmNAmjsHke4pd8S9z6m_hVRur.html

    • @alexyu8951
      @alexyu8951 Před 3 lety

      Thx

  • @pablodavidclavijo4609
    @pablodavidclavijo4609 Před 3 lety +1

    I love the jazz music stops vibe given by having jazz music literally stopping

  • @davecolwell725
    @davecolwell725 Před 3 lety

    4:05 I finally understand how gravity works on our planet. Omg. That was the best explanation I’ve ever seen.

  • @Zagardal
    @Zagardal Před 3 lety +3

    I'm at an approximate 2.5, if I had to quantify it, and when I talk about this to people in lower levels, they feel like I'm a genius, even tho I tell them I basically know nothing. It's wild how the depth of knowledge is so overwhelming that even a slight amount of it can make you look way smarter than you actually are to people who just used their time learning other things.

    • @YuvrajBachira
      @YuvrajBachira Před 2 lety +1

      Yeah, same with me. I hate appreciations. Whenever I tell people about such things, they start feeling like I'm a genius. But it feels strange and Little bit funny when most people don't know about the reality ( i mean the beauty of maths and physics) . Why most of people do boring jobs and why they want to become rich? We will die at the end so do some interesting.
      I don't want to live a normal life😅 but my parents are forcing (a little bit) to do some government job or any job.
      Sharing my thoughts with others feels good :)

    • @Zagardal
      @Zagardal Před 2 lety +1

      Having conversations you wouldn't normally have can really help to put some things into perspective.